Développement et Implémentation d’Algorithmes de Tatouage Numérique des Données Multimédia

Abstract

In this thesis, we give a deep overview of digital video watermarking and present two contributions in this domain. In the first contribution, we propose a robust video watermarking scheme based on spatiotemporal just noticeable distortion in the DCT domain. Spatiotemporal Just noticeable distortions (ST-JND) which refers to the maximum distortion threshold that the HVS cannot perceive is employed in order to obtain a trade-off between watermark robustness and imperceptibility. The STJND based video watermarking algorithm achieves better performance compared to a no-HVS approach and S-JND approach. In the second contribution, we overcome the problem of a frame-byframe embedding technique by choosing only the frames that have big motion energy to be the host frames. By doing so, the number of frames to be processed is consequently reduced and a better quality of the watermarked video is ensured since the human visual system cannot notice the variations in fast moving regions. The experimental results show that the proposed method can achieve a very good transparency while being robust against various kinds of attacks. Compared to several methods found in the literature, the proposed method gives a better robustness.